Highest averages methodA highest-averages method, also called a divisor method, is a class of methods for allocating seats in a parliament among agents such as political parties or federal states. A divisor method is an iterative method: at each iteration, the number of votes of each party is divided by its divisor, which is a function of the number of seats (initially 0) currently allocated to that party. The next seat is allocated to the party whose resulting ratio is largest.
Système électoralthumb|400px|Système électoral utilisé pour élire la chambre basse par pays. Système majoritaire Système semi-proportionnel Système proportionnel Système mixte Autre Le 'système électoral, mode de scrutin', système de vote ou régime électoral, désigne tout type de processus permettant l'expression du choix d'un corps électoral donné, souvent la désignation d'élus pour exercer un mandat en tant que représentants de ce corps (élection), ou moins souvent le choix direct (référendum) d'une option parmi plusieurs.
Hare quotaThe Hare quota (also known as the simple quota) is a formula used under some forms of proportional representation. In these voting systems the quota is the number of votes that guarantees a candidate, or a party in some cases, captures a seat. The Hare quota is the total number of votes divided by the number of seats to be filled. This is the simplest quota, but the Droop quota is mostly used currently. The Hare quota can be used in the single transferable vote (STV-Hare) system and the largest remainder method (LR-Hare) and other quota rule compatible methods of party-list proportional representation.
Imperiali quotaThe Imperiali quota is a formula used to calculate the minimum number, or quota, of votes required to capture a seat in some forms of single transferable vote or largest remainder method party-list proportional representation voting systems. It is distinct from the Imperiali method, a type of highest average method. It is named after Belgian senator Pierre Imperiali. The Czech Republic is the only country that currently uses this allocation system, while Italy and Ecuador used it in the past.
Apportionment (politics)Apportionment is the process by which seats in a legislative body are distributed among administrative divisions, such as states or parties, entitled to representation. This page presents the general principles and issues related to apportionment. The page Apportionment by country describes specific practices used around the world. The page Mathematics of apportionment describes mathematical formulations and properties of apportionment rules. The simplest and most universal principle is that elections should give each voter's intentions equal weight.
Quota ruleIn mathematics and political science, the quota rule describes a desired property of a proportional apportionment or election method. It states that the number of seats that should be allocated to a given party should be between the upper or lower roundings (called upper and lower quotas) of its fractional proportional share (called natural quota). As an example, if a party deserves 10.56 seats out of 15, the quota rule states that when the seats are allotted, the party may get 10 or 11 seats, but not lower or higher.
D'Hondt methodThe D'Hondt method, also called the Jefferson method or the greatest divisors method, is an apportionment method for allocating seats in parliaments among federal states, or in proportional representation among political parties. It belongs to the class of highest-averages methods. The method was first described in 1792 by future U.S. president Thomas Jefferson. It was re-invented independently in 1878 by Belgian mathematician Victor D'Hondt, which is the reason for its two different names.
Apportionment paradoxAn apportionment paradox exists when the rules for apportionment in a political system produce results which are unexpected or seem to violate common sense. To apportion is to divide into parts according to some rule, the rule typically being one of proportion. Certain quantities, like milk, can be divided in any proportion whatsoever; others, such as horses, cannot—only whole numbers will do. In the latter case, there is an inherent tension between the desire to obey the rule of proportion as closely as possible and the constraint restricting the size of each portion to discrete values.
Leveling seatLeveling seats (tillægsmandat, utjämningsmandat, utjevningsmandater, jöfnunarsæti, Ausgleichsmandat), commonly known also as adjustment seats, are an election mechanism employed for many years by all Nordic countries (except Finland) in elections for their national legislatures. In 2013, Germany also introduced national leveling seats for their national parliament, the Bundestag. The electoral reform in Germany 2023 removed the leveling seats, and replaced with Zweitstimmendeckung.
Scrutin proportionnel plurinominalLe mode de scrutin proportionnel plurinominal (également appelé représentation proportionnelle à scrutin de liste, RPSL) est un système électoral où le nombre de sièges à pourvoir est partagé en fonction du nombre de voix recueillies. C'est le système électoral proportionnel le plus répandu parmi les États indépendants et les territoires semi-autonomes qui tiennent des élections parlementaires au scrutin direct. Il est né au avec l'apparition des partis politiques.
